Summaries in Afrikaans and English / Afrikaans text / Die doel van hierdie studie was om argivale inligtingontsluiting en -herwinning aan die einde van die 20ste eeu te ondersoek, verai met betrekking tot ernstige historiese navorsing. Inligting is op die volgende wyses ingesamel: ‘n uitgebreide literatuurondersoek, onderhoude met argivarlsse in beide staats- en privaatargiefbewaarpiekke en ‘n empiriese ondersoek deur middel van ‘n vraelys wat aan hoofsaaklik ernstige historiese navorsers versprei is. Die navorser het argivale vindmiddels soos inventarisse, gidse en indekse, sowel as die gerekenariseerde argivale databases, persoonlik ondersoek ten einde eerstehandse kennis van die voordele en nadele van hierdie navorsings- hulpmiddets te verkry. Daar is gevind dat tegnologiese ontwikkelings die aard van argiefbewaarplekke en argivale bronne verander het. Die impak van rekenaarnetwerke op die argivale milieu, sowel as die voor- en nadele verbonde aan die hantering van elektroniese argivale rekords en mondelinge geskiedenisargiewe, is gevolglik in besonderhede bespreek, Hoewel die ontsluiting van argivale bronmateriaai steeds op die beginsels van herkoms en oorspronklike orde gebaseer is, is sekere aanpassings noodsaaklik. Tog is geen toegang tot argivale inligtingbronne sonder hie rdie prosesse moontlik nie, Doeltreffende argivale inligtingherwinning kan slegs verwesenlik word indien genoeg fondse en opgeleide, ervare personeel beskikbaar gestel word. Vervolgens Is die veranderende aard van historiese navorsing belig, verat wat die keuse van ondemverpe betref. Moderne tendense ten opsigte van die geskiedenis van benede, of die geskiedenis van die aiiedaagse lewe, en die geskiedenis van vroue, in teenstelling met tradisionele historiese nadruk op politieke figure en gebeure, is bespreek. Die studie het verder aangetoon dat toeganklikheid tot argivale inligtingbronne die belangrikste behoefte van die historiese navorser is. Die beduidende rol wat die argivaris en argivale vindmiddels in historiese navorsing speel, is beklemtoon. Gedurende die empiriese fase is 'n ontleding van die antwoorde van respondente ten opsigte van navorsingsbesoeke aan argiefbewaarplekke gedoen, Historiese navorsers se ondervinding met betrekking tot argivale vindmiddels, gerekenariseerde argivale netwerke en leeskamerpersoneel is bespreek. Die ondersoek word afgesluit met beiangrike bevindings en 'n aantal aanbevelings rakende historiese navorsing as ‘n argivale aktiwiteit in 'n veranderende inligtingwereld. / The purpose of this study was to investigate archival information organisation and retrieval at the end of the 20th century, especially with regard to serious historical research. Information was collected by the following means: an extensive literature survey, interviews with archivists in both state and private archives and an empirical survey by means of a questionnaire distributed amongst mainly serious historical resea rchers.The researcher personally examined archival finding aids such as inventories, guides and indexes, as well as the computerised archival database, for firsthand knowledge of the advantages and disadvantages of these research aids. It was found that technological developments had changed the nature of archives and archival sources, the most important adjustment being to electronic information sources and oral history archives. The impact of computer networks on the archival milieu, as well as the advantages and disadvantages of dealing with electronic archival records and oral history archives, was subsequently discussed in detail. Although the organisation and description of archival source material are still based on the principles of provenance and original order, certain adaptations are necessary. Without these processes no access to archival sources is possible. Effective archival information retrieval can only be achieved if sufficient funds are made available and well-trained, experienced staff are appointed. Subsequently the changing nature of historical research, especially with regard to the choice of research topics, was discussed. Modern tendencies such as history from below, or the history of everyday life, and the history of women, were investigated, in opposition to traditional historical emphasis on important political figures and happenings. Research further showed that accessibility to archival information sources is of paramount importance to the historical researcher. The important role of the archivist and archival finding aids, is emphasised. During the empirical phase the answers of respondents about their visits to archives were analysed. The experiences of historical researchers with regard to archival finding aids, computerised archival networks, and reading room staff, are discussed. The study is concluded with important findings and a number of recommendations pertaining to historical research as an archival activity in a changing information world. / Information Science / D. Litt. et Phil. (Information Science)

The gemological collection of Abraham Gottlob Werner contains 1374 sample numbers for 25 different minerals with 38 gemological varieties, including 15 newly added numbers of samples, which were not recorded in the original catalog of 1823. In total, 168 samples were recorded as lost by the later researchers, 4 samples were taken for the chain for the rector of the university, samples of 2 different numbers in the catalog were exchanged for cut stones, and 3 times’ volume requisitions happened. A total of 256 sample numbers show discrepancies and therefore are not in accordance with the original record in the catalog. In the collection, 6.8% of the numbers are rock sample with embedded crystals, 20.7% of the numbers are in the form of crystal, 30.6% of the numbers are fragments, 11.6% of the numbers are grains, and the remaining 711 samples are cut. Except for Esa. No. 644a containing four cushion cut samples, all faceted cuts were recorded in the original catalog of 1823. However, the brilliant, oval, step, emerald, scissor, and radiant cut forms were invented after the gemological collection of Werner, which means 189 samples do probably not belong to the original collection. They could be from another collection due to the requisitions, or the later researchers of the collection added or exchanged the samples with new ones. The mineral names of the catalog from 1823 refer to Werner's mineral system, some of the mineral's names are not used anymore. With the development of mineralogy and gemology, the special names of the gemstones as varieties of minerals are gradually standardized. 51 samples are wrong identifications and 8 pieces of glass have been recognized. The zircon samples of the collection provide a research resource for the study of metamictization. Both color and density of zircon could be an indicator of the metamictization degree. The metamictization has a significant influence on the gemological properties of zircon. The green tone and low density cannot be considered as an identifying characteristic of metamict zircon, although they are still a sign of metamictization. Comparing six mineralogical or geological collections at Werner’s time, the catalogs of five collections used his nomenclature of samples and only the catalog of the mineralogical collection of Adolf Traugott von Gersdorf is geographical. To his time the outstanding gemological collection of Abraham Gottlob Werner represented the broadest quantity of gemological varieties. A modern gemological database of the collection has been founded, the meta-data provides an important base for further research and development.:Acknowledgements I Abstract III Table of Contexts IV List of figures VI List of tables VII 1. Introduction 1 1.1 Abraham Gottlob Werner 1 1.2 The mineral system of Werner 1 1.3 The gemological collection of Werner 3 2. Methods 6 2.1 Specific gravity (SG) measurements 6 2.1.1 Hydrostatic weighing 6 2.1.2 He-pycnometer 6 2.2 Color 6 2.2.1 Munsell color system 7 2.2.2 The CIE L*C*h color system 8 2.3 The optical measurements 9 2.3.1 Polariscope 9 2.3.2 Refractometer 10 2.3.3 Dichroscope 11 2.4 Ultraviolet (UV) fluorescence test 12 2.5 Raman spectroscopy 12 3. New model for the inventory of the gemological collection of Werner 13 4. Discussion 16 4.1 Cut cutting in the course of time 16 4.2 Classification of gemstones 24 4.2.1 Individual names of gemstones 25 4.2.2 Different identifications with the catalog of 1823 29 4.2.3 Imitation of gemstones 31 4.3 Raman spectrum study of zircons 32 4.4 Comparison of the outstanding Werner Collection with other collections in the second half of 18th century 39 4.4.1 The natural history collection of Linck family (1638-1807) 39 4.4.2 The Minerals cabinet of Eugen Pabst von Ohain (1718-1784) 40 4.4.3 The natural history collection of the University of Rostock 40 4.4.4 The mineralogical collection of Adolf Traugott von Gersdorf (1744-1807) 41 4.4.5 The mineralogical, geological and paleontological collection of Johann Wolfgang von Goethe (1749-1832) 42 4.4.6 Summary of the additional collections to Werner's time 43 5. Summary 44 Reference 46 Appendix A 59 Appendix B 63 Appendix C 67

Authority control is the backbone of the library catalogue and therefore a critical library activity. Experienced staff create authority records to assist users in their quest for information. The focus of this study is on authority control as a means of co-operation in academic library consortia using a union catalogue maintained by a Central Office for Authority Control. Literature studies were conducted on three sub-problems: the development of academic library consortia in South Africa, and various forms, characteristics and functions of academic library consortia in general; the characteristics, principals and objectives of authority control; and the functions of union catalogues with special reference to the role of Z39.50 within virtual union catalogues. The conclusion was that existing and new authority records should be made available as widely as possible within consortia through a union catalogue. It is however a partial solution, because not all the libraries within the consortium have the expertise to create new authority records. Two empirical studies were conducted. A cost analysis was done to determine the cost of creating and changing authority records within academic library consortia in South Africa, in order to choose a system within which authority control can be performed effectively and speedily. Secondly, a questionnaire was sent to libraries in the United States to gather information on their experiences with regard to authority control, library co-operation in general, and virtual union catalogues. The United States was the natural choice because it could be regarded as the birthplace of modern library consortia. Inferences drawn from the information received was used to develop the structure and functions for a Central Office for Authority Control in academic library consortia in South Africa. It was found that authority control within an academic library consortium using a union catalogue could be conducted most cost-effectively and timeously through such a Central Office for Authority Control. The purpose of the Central Office would be to co-ordinate authority control within the consortium. Pooling available resources within the consortium would keep the cost of authority control as low as possible. Libraries with the required infrastructure and expertise would have the opportunity to create authority records on behalf of other libraries and be compensated for their services. Through such a Central Office more authority records created according to mutually accepted standards would be available for sharing within the consortium. / Information Science / D.Litt. et Phil. (Information Science)